The present invention relates to a reception apparatus, a reception method, a transmission apparatus, a transmission method, a transmission-reception apparatus, and a transmission-reception method. More particularly, the invention relates to a program selection support apparatus, a program selection support method, a reception apparatus, a reception method, a transmission apparatus, a transmission method, a transmission-reception apparatus, and a transmission-reception method whereby information edited for specific viewers is transmitted, received and reproduced.
Recent advances in information compression technology combined with novel data transmission channels having greater capacities and affording higher transmission speeds have made it possible to transmit an increasingly large number of programs to viewers. With more programs to choose from, the so-called program selection support apparatus is now playing an important role in helping viewers to select desired programs.
The program selection support apparatus illustratively displays the viewing fee of any designated program, the broadcast time of the designated program, type of information to be broadcast (e.g., images, voice, data), a plot of the program, and a list of programs to be broadcast on specific days, so that viewers may select desired programs with ease.
By referencing the past viewing history of each viewer, the program selection support apparatus may retrieve and display personalized information (message) edited by the broadcasting side.
FIG. 15 is a block diagram outlining the constitution of a related art digital television broadcast transmission apparatus. In this block diagram, personalized information is information which is edited by the broadcasting side for specific viewers. For example, personalized information may include key information for allowing a specific viewer to descramble scrambled programs and a message addressed by the broadcasting side to that viewer. General-public-oriented information is information which may be received by all viewers, and illustratively includes EPG (electrical program guide) information for supporting program selection.
In FIG. 15, a processing unit 1 comprises a CPU (central processing unit) 1a, a ROM (read only memory) 1b, a RAM (random access memory) 1c and an interface (IF) 1d. The processing unit 1 controls the apparatus as a whole and performs various computations. A modem 2 receives information through a telephone line from viewers (e.g., information indicating that a specific program has been viewed, information for making a merchandise purchase contract, etc.), demodulates it, and supplies the demodulated information to the processing unit 1.
A personalized information generating unit 3 generates personalized information. An encryption unit 4 encrypts personalized information. A general-public-oriented program information generating unit 6 generates program information destined for the general public. A composing unit 5 composes personalized information from the encryption unit 4 and general-public-oriented program information from the general-public-oriented program information generating unit 6.
An audio visual information generating unit 8 generates information about a plurality of programs composed of images, voice and data (i.e., audio visual information) and, if necessary, scrambles information about specific programs. A composing unit 7 composes information from the audio visual information generating unit 8 and information from the composing unit 5. A transmitting unit 9 transmits information from the composing unit 7 to viewers. A database 10 stores information about subscription contracts with viewers, about their viewing history, and other information.
Personalized information is encrypted by the encryption unit 4 to ensure security. This means that encrypted personalized information is used only by specifically authorized viewers.
FIG. 16 is a block diagram outlining the constitution of a related art program selection support apparatus on the receiving side (i.e., an apparatus for receiving signals sent by the apparatus of FIG. 15) In FIG. 16, a tuner 21 receives information from the broadcasting side and forwards the received information to a separation processing unit 22. The separation processing unit 22 separates the received information into personalized information, general-public-oriented information and audio visual information. A decoder decodes (i.e., deciphers) encrypted personalized information so as to extract a message and key information therefrom.
FIG. 17 is a view of a typical data structure of related art personalized information containing a message and key information. As illustrated, a message 42 and key information 43 are each included independently in personalized information 41.
A display unit 24 is arranged to display the message 42 extracted by the decoder 23. Typically, the display unit 24 may be a CRT (cathode ray tube) display unit or an LCD (liquid crystal display) unit.
An audio visual processing unit 25 selects information about any specific program from the audio visual information separated by the separation processing unit 22, so as to extract audio and visual information included in the program information. When necessary, the audio visual processing unit 25 descrambles the information about a specific program. A display unit 26 displays visual information supplied from the audio visual processing unit 25 or from a processing unit 28. The display unit 26 has the same constitution as the display unit 24 mentioned above. In this respect, the two display units may be replaced by a single unit that performs the functions of both. A speaker unit 27 converts an audio signal from the audio visual processing unit 25 or processing unit 28 into voice.
As shown in FIG. 18, the processing unit 28 comprises a CPU 51, a ROM 52, a RAM 53 and an interface (IF) 54. Constituted as such, the processing unit 28 controls the apparatus as a whole and performs various computations.
A storage unit 29 stores as needed general-public-oriented program information (EPG information) transmitted from the broadcasting side. An input unit 31, illustratively composed of a keyboard, a mouse and a remote controller, is operated by viewers when they wish to input information. A modem 32 modulates data from the processing unit 28 into a predetermined signal for transmission over a telephone line to the broadcasting side in FIG. 15.
The program selection support apparatus constituted as described works as follows:
There may occur a case where the broadcasting side needs to transmit some information to a specific viewer or a case where the broadcasting side is requested by a specific viewer to send some information thereto. In such cases, the CPU 1a of the broadcast transmission apparatus in FIG. 15 supplies a predetermined control command to the personalized information generating unit 3 and causes the latter to generate personalized information 41. The personalized information 41 thus generated is encrypted by the encryption unit 4.
Concurrently, the CPU 1a feeds if necessary a predetermined processing command to the general-public-oriented program information generating unit 6 and causes the latter to generate program information destined for the general public. The encrypted personalized information 41 and the general-public-oriented program information are composed by the composing unit 5. The composed result is sent from the composing unit 5 to the composing unit 7.
While broadcasting is in progress, the audio visual information generating unit 8 generates a plurality of programs each constituted by images, voice and data and feeds the programs to the composing unit 7. If necessary, the audio visual information generating unit 8 scrambles specific programs. In that case, the CPU 1a retrieves key information from the database 10 or the like and sends the key information to the audio visual information generating unit 8. On the basis of the key information thus supplied, the audio visual information generating unit 8 scrambles specific program information.
In addition, the CPU 1a retrieves from the database 10 personalized key information (which differs from one viewer to another) for descrambling the scrambled program information. The personalized key information thus retrieved is output to the personalized information generating unit 3.
The personalized information generating unit 3 supplements the personalized information 41 with the personalized key information furnished as key information 43 before the personalized information 41 is output. On the basis of the key information 43 thus added, the audio visual information generating unit 8 scrambles appropriate programs.
When the receiving side is to reproduce any scrambled program (i.e., descramble the program), the key information 43 included in the personalized information 41 is first extracted. The extracted key information is used as the basis for descrambling the desired program.
The program information fed from the audio visual information generating unit 8 and the information from the composing unit 5 are composed by the composing unit 7. The composed result is transmitted to viewers from the transmitting unit 9 over radio waves or through cables.
The information sent from the broadcasting side is received by the tuner 21 on the receiving side in FIG. 16. The received information is fed to the separation processing unit 22. The separation processing unit 22 separates the received information into personalized information 41, general-public-oriented program information and audio visual information. The personalized information 41, general-public-oriented program information and audio visual information acquired from the separation process are supplied respectively to the decoder 23, processing unit 28 and audio visual processing unit 25.
The encrypted personalized information 41 is decoded by the decoder 23. A message 42 and key information 43 are extracted from the decoded information. The message 42 is forwarded to the display unit 24 for display thereon. For example, a displayed message informs the viewer that the viewing fee for a pay-per-view program having been watched is yet to be paid.
The key information 43 is supplied to the processing unit 28. In the processing unit 28, the key information 43 is stored illustratively in the RAM 53.
The general-public-oriented program information separated by the separation processing unit 22 is fed via the processing unit 28 to the storage unit 29. The storage unit 29 stores as data the general-public-oriented program information thus supplied.
Suppose that a viewer inputs a command of an EPG display through the input unit 31 to search for information about a desired program. In such a case, the command thus entered is fed to the processing unit 28. In response to the input command, the CPU 51 of the processing unit 28 reads an EPG from the storage unit 29 for display onto the display unit 26. The viewer finds the desired program from the display (EPG).
After referring to the EPG and deciding on the program to be viewed, the viewer makes necessary input operations from the input unit 31 to select the program in question. The CPU 51 of the processing unit 28 detects the viewer's input and accordingly supplies the audio visual processing unit 25 with a control command for selecting the appropriate program. In accordance with the control command, the audio visual processing unit 25 extracts audio and visual information about the designated program and sends visual information to the display unit 26 and audio information to the speaker unit 27. This initiates reproduction of the program.
Where the program is scrambled, the CPU 51 reads key information 43 from the RAM 53 and supplies it to the audio visual processing unit 25. Given the key information 43, the audio visual processing unit 25 descrambles the program in question and feeds descrambled visual and audio information to the display unit 26 and speaker unit 27 respectively for program reproduction.
With the above program selection support device in use, viewers can get EPG's displayed, find desired programs therefrom, and invoke information about any specific program so that the desired program may be selected on the basis of the furnished information.
One disadvantage of the related art program selection support apparatus is that the EPG (electronic program guide) is simply general-public-oriented program information; all viewers are fed with the same EPG. This makes it difficult for individual viewers to select their desired programs quickly and unfailingly.